(57) In a video camera having an automatic focusing function, a focus evaluating value
is calculated as the sum of first and second focus evaluating values extracted using
outputs of two filters having different cut-off frequencies, and a relative ratio
of the first and second focus evaluating value is also calculated. This relative ratio
is compared with a predetermined reference value. Considering a case in which the
focus evaluating value is below this reference value after an object is brought into
focus, even if the focus evaluating value does not change, an auto-focus operation
is resumed. On the other hand, considering a case in which the relative ratio is above
the reference value, even if the focus evaluating value changes, the auto-focus operation
is not resumed. In addition, even if the focus evaluating value reaches a maximum
in the auto-focus operation, the auto-focus operation is not terminated if the relative
ratio does not reach a predetermined reference value. Furthermore, the amount of slight
movement of a lens in an object change confirming operation after bringing the object
into focus is switched depending on the relative ratio. Additionally, it is determined
whether or not the lens correctly moves toward an in-focus position by determining
the increase or decrease of the relative ratio.
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